Add histograms for MouseEventPrefetch.Mouse*

Add histograms for MouseEventPrefetch.Mouse*

BUG=234036
NOTRY=true

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=198716

[kouhei (in TOK), 2013-05-07 01:22:58]

Could you review this patch?

[Ilya Sherman, 2013-05-07 02:41:10]

https://codereview.chromium.org/15027003/diff/1002/tools/metrics/histograms/h...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/15027003/diff/1002/tools/metrics/histograms/h...
tools/metrics/histograms/histograms.xml:1098: links' default click events
without prior mousedown events.
It seems like you'd derive some benefit by creating a custom enumeration rather
than trying to recycle BooleanHit here.

https://codereview.chromium.org/15027003/diff/1002/tools/metrics/histograms/h...
tools/metrics/histograms/histograms.xml:1105: event handler.
Does this histogram just have a single bucket?  If so, how do you plan to
interpret the numbers?  For example, suppose you see a billion mouse-downs
reported in a day.  How will that number be actionable?

[kouhei (in TOK), 2013-05-07 03:37:03]

Updated patch. Could you review?

https://codereview.chromium.org/15027003/diff/1002/tools/metrics/histograms/h...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/15027003/diff/1002/tools/metrics/histograms/h...
tools/metrics/histograms/histograms.xml:1098: links' default click events
without prior mousedown events.
On 2013/05/07 02:41:10, Ilya Sherman wrote:
> It seems like you'd derive some benefit by creating a custom enumeration
rather
> than trying to recycle BooleanHit here.

Done.

https://codereview.chromium.org/15027003/diff/1002/tools/metrics/histograms/h...
tools/metrics/histograms/histograms.xml:1105: event handler.
The number will be compared to the hits of MouseOverFollowedByClick. The ratio
of MouseOver events followed by click over total num. of MouseOver events can be
calculated.

[Ilya Sherman, 2013-05-07 08:52:23]

LGTM with nits.

https://codereview.chromium.org/15027003/diff/5001/tools/metrics/histograms/h...
File tools/metrics/histograms/histograms.xml (right):

https://codereview.chromium.org/15027003/diff/5001/tools/metrics/histograms/h...
tools/metrics/histograms/histograms.xml:1099: links' default click events
without prior mousedown events.
Optional nit: I think this description would be easier to understand if it were
worded something more like:

"For each click handled by an HTML anchor tag link, whether Blink [or some other
system?] saw a mousedown event preceding it.  This is only measured for clicks
handled by the anchor tag's default click event handler."

https://codereview.chromium.org/15027003/diff/5001/tools/metrics/histograms/h...
tools/metrics/histograms/histograms.xml:9405: <int value="0"
label="Caught_event_before_click"/>
nit: No need for underscores; you can use spaces.  This is a human-readable
label.

https://codereview.chromium.org/15027003/diff/5001/tools/metrics/histograms/h...
tools/metrics/histograms/histograms.xml:9406: <int value="1"
label="Miss_event_before_click"/>
Ditto.  Also, probably "Missed" rather than "Miss"

[kouhei (in TOK), 2013-05-07 09:22:45]

Thank you for review! fixed nits.

[commit-bot: I haz the power, 2013-05-07 09:22:58]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/kouhei@chromium.org/15027003/10001

[commit-bot: I haz the power, 2013-05-07 13:59:29]

Change committed as 198716